Can concentric reducers be used in place of eccentric reducers?
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The newly installed unit is undergoing the three inspections and four adjustments, but many of the eccentric tees shown on the PID diagram are actually concentric at the site. I’m not sure if this is acceptable; could those involved in the design please help check whether it’s okay?
It depends on where it is used; this question can’t be answered in a general way. Some items can be interchanged, while those that are critical cannot be swapped
According to the section on reducing fittings in Part 2 of the \"Design Manual for Pipeline Installation in Petrochemical Plants\": unless there are special requirements, concentric reducers are generally used for vertical pipes, while eccentric reducers are used for horizontal pipes. The orientation of the eccentric large and small ends is based on the principle that no air pockets or liquid pockets should form in the pipe section where the eccentric large and small ends are located. Usually, when the larger end of the eccentric fitting is connected to the horizontal pipe at the upper part of the standpipe, the eccentric fitting should be level at the bottom ； When the riser connects to the horizontal pipe at the lower part, the eccentric reducer should be level on top.
What was said upstairs makes sense; the key is where it is used. The relatively critical issue is at the pump inlet